PEARL, RAYMOND

(b. Farmington, New Hampshire, 3 June 1879; d. Hershey, Pennsylvania, 17 November 1940)

biology, genetics.

Pearl was the only child of Frank Pearl and Idea May McDuffee. He attended public schools in Farmington and nearby Rochester. In 1899 he earned the A.B. in biology at Dartmouth College and the Ph.D. in 1902 at the University of Michigan, where his dissertation was on the behavior of a flatworm (Planaria). He also studied at the University of Leipzig in 1905 and at University College, London, from 1905–1906. In London he studied under Karl Pearson, whose influence led Pearl to apply statistics to population studies.

Pearl was an instructor in zoology at the University of Pennsylvania (1906–1907) until he became chairman of the department of biology at the Maine Agricultural Experiment Station (1907–1918), where he studied the heredity and reproduction of poultry and cattle. As chief of the statistical division of the U.S. Food Administration from 1917 to 1919, he studied the relationship of food to population. Pearl’s long association with the Johns Hopkins University began in 1918, when he became professor of biometry and vital statistics in the School of Hygiene and Public Health (1918–1925). He was also professor of biology in the School of Medicine (1923–1940), research professor and director of the Institute of Biological Research (1925–1930), and statistician at the Johns Hopkins Hospital (1919–1935).

A prodigious researcher and a voluminous and articulate writer, Pearl achieved renown as a pioneer in world population changes, birth and death rates, and longevity. He founded and edited the Quarterly Review of Biology from 1926 and Human Biology from 1929. On 29 June 1903 he married Maud Mary DeWitt, who assisted his researches and writing; the couple had two daughters, Ruth DeWitt and Penelope Mackey.

Pearl attracted public attention in 1920 with a mathematical equation for determining population to the year 2100. His predictions deviated only 3.7 percent in the 1940 census. His other research findings, often controversial, led him to believe that the length of life varied inversely with the tempo or pace of living, that heredity predominated over environment in the length of life and in shaping one’s destiny, that moderate drinkers lived longer than total abstainers, and that intellectuals had a better chance to live longer than did manual workers. In one study he analyzed the reproductive histories; the use of contraception; and the social, economic, educational, health, and religious histories of 30,949 mothers.

Pearl received many honorary degrees for his work relating biology to the social sciences. He was president of the International Union for Scientific Investigation of Population Problems (1928–1931), the American Association of Physical Anthropologists (1934–1936), and the American Statistical Association (1939). He was also made a knight (1920) and an officer (1929) of the Crown of Italy.

Obituary accounts called Pearl “a statistician of the human race” and a “biologist-philosopher.” H. L. Mencken praised his lucid writing style, his wide knowledge and interests, his scientific creativity, and his delight in playing the French horn.

BIBLIOGRAPHY

I. Original Works. Pearl’s writings include Modes of Research in Genetics (New York, 1915); Diseases of Poultry (New York, 1915), written with F. M. Surface and M. R. Curtis; The Nation’s Food (Philadelphia, 1920); The Biology of Death (Philadelphia, 1922); Introduction to Medical Biometry and Statistics (Philadelphia-London, 1923; 3rd ed. 1940); Studies in Human Biology (Baltimore, 1924); The Biology of Population Growth (New York, 1925); Alcohol and Longevity(New York, 1926); To Begin With (New York, 1927; rev. 1930); The Rate of Living (New York, 1928); Constitution and Health (London-New York, 1933); The Ancestry of the Long-Lived (Baltimore, 1934), written with Ruth DeWitt Pearl; and The Natural History of Population (London-New York, 1939). He was editorial associate of Biometrika, Journal of Agricultural Research, Genetics, Metron, Biologia generalis, and Acta biotheoretica.

II. Secondary Literature. Biographical and obituary accounts are A. W. Freeman, “Raymond pearl, 1879–1940,” in American Journal of Public Health,31, no. 1 (1941), 81–82; H. S. Jennings, “Raymond Pearl, 1879–1940,” in Biographical Memoirs. National Academy of Sciences,22 (1943), 295–347, which includes a full bibliography; H. L. Mencken, in Baltimore Sun (24 Nov. 1940); J. R. Miner and J. Berkson, “Raymond Pearl, 1879–1940,” in Scientific Monthly,52 (1941), 192–194; “News and Notes,” in American Journal of Sociology,16, no. 4 (1941), 604; and Dictionary of American Biography, XXII, supp. 2 (1958), 521–522.

Franklin Parker